Artificial limb



Feb. 20, 1951 w. G. FARRAR, JR 2,542,316

ARTIFICIAL LIMB Filed Dec. 23, 1946 5 Sheets-Sheet l William 6. Farm; Jr.

Feb. 20, 1951 w. m. FARRAR. JR 2,542,316

ARTIFICIAL LIME Filed Dec. 23, 1946 3 $heets-Sheet 2 Fig. 2.

Feb 20 1951 w. FARRAR, JR 2,

ARTIFICIAL mm Filed Dec. 23, 1946 3 Sheets-Shet a William 6. Farrar; J1:

Patented Feb. 20, 1951 UNITED STATES PATENT OFFICE ARTIFICIAL LIMB William G. Farrar, Jr., Ottawa, Ill. Application December 23, 1946, Serial No. 718,076

' The present invention relates to new and useful improvements in artificial limbs and more particularly to an artificial hand and wrist.

- An important object of the invention is to provide an artificial limb of this character that has a natural appearance and which yields to the grip of others to provide the eifect of a normal hand.

v A further object of the invention is to provide means controlled by the movement of the arm of a person to open and close the fingers of the artificial hand.

"An additional object is to provide a universal movement for the wrist portion of the artificial limb.

iA still further object is to provide an artificial hand and wrist including a rigid skeleton frame for the hand encased in resilient material such as rubber or the like which will yield to the touch and also providing means for normally maintaining the artificial hand in an extended lposition and operable to close the fingers by a predetermined movement of the arm to whichthe artificial hand is attached.

Another object is to provide a device of this character of simple and practical construction, which is neat and attractive in appearance, relatively inexpensive to, manufacture and otherwise well adapted for the purposes for Which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which: v

Figure l is a front elevational view of the artificial' limb and showing the harness attached in position to the arm of a person. I

Figu 'e 2 is an enlarged sectional view of the hand and wrist of the artificial limb.

"Figure 3 is a sectional view taken on a line 33 of Figure 2.

Figure 4 is a group perspective view of one of the finger joints.

T'Figure 5 is an elevational view of the outer 5 Claims. (Cl. 3-12) I closed a preferred embodiment of the invention infer the purpose of illustration I have dis-" the numeral 5 designates a rigid skeleton frame for an artificial hand and which is preferably constructed of light weight metal, the side edges of the frame being curved inwardly as shown at 5 to provide a desired thickness therefor. The frame 5 is enclosed in a covering of molded material I, such as flexible rubber or other suitable material having comparatively little porosity, the covering being shaped into the form of an artificial hand to include the fingers 8 and thumb 9.

Each of the fingers B and thumb 9 is provided with a reinforcing core designated generally at lil embedded therein, the cores for the several fingers being of identical construction and accordingly a detailed explanation of one will suffice for all. Each of the cores includes inner and outer phalanges I! and I2 and an intermediate phalange l3 representing the several phalanges of the finger. The inner phalange II is formed with eyes I4 and I5 and at its ends, the eye [4" being aligned with an eye It, the latter being formed with a bifurcated extension l1 welded or otherwise suitably secured to an edge of the frame 5. l'he aligned eyes l4 and I6 are pivoted to each other by means of a pin IS. The

eye I4 is formed with a rearwardly extending stop l9 engaging a stop 20 on the eye [6 to pre-- 25 cooperating to prevent backward pivotal. move ment of the phalange [3.

The inner end of the phalange I2 is formed with an eye 26 al gned with the eye 2| of the intermediate phalange l3 and pivoted thereto with a pin 21 and the eyes 2| and 26 are also formed with stops 2'! and 28.

The frame 5 adjacent each knuckle phalange is provided with a pin 29 and laterally projecting pins Sll are also provided adjacent each end of the phalanges II and I3 and at the inner end of the phalange l2, the pins having coil springs 3| attached thereto for connecting the several phalanges to each other at their pivoted ends and for connecting the inner phalange I l to the frame, the springs being arranged to maintain, the cores in an extended position and to thus straighten the fingers B.

The core for the thumb 9 is similarly. con-t ceived, such as. piano wire, the end of; the wirev being attached in any suitable manner to a his 36 adjacent the outer ends of the outer pha- The wires 35 for the several fingers langes l2. extend to guides 37 suitably secured to thefront surface of the frame and all of the wires extend through a guide tube 38 secure'dtothe-frame 5 and extending outwardly through the-wristzpontion 39 of the hand on th inside of the wrist as shown in Figure 1.

The wires 35 then extend rearwardly through aguide 48 carried by a: forearm strap or harness 41 and'the rear ends of the wires are then. at-

tached to a plate 42 carried by a strap or-harness.

43; secured to the upper arm-of a person. The

coil-springs ii; are interposedin the severalwires adjacent their inner ends.

The resilient wrist portion 39 isof tubular-construction and telescopes overa rigid socket 45 in which. the stump of the forearm is received and secured in position by the-harness! l.

The outer'end of the socket 45 is formedzwith a bracket it having a pair of aligned eyes. and

in which the smooth. ended pins or bolts :48 are threaded, the inner ends of' the pins having-the opposite edges of 'a' plate 49 pivotally attached thereto. The plate 49 is provided with a pin or rivet 5E3 extending-therethrough at right'angles tothe pins 63 and on the end of which aayoke: v 5! is pivotally mounted, the yoke projecting rear-- wardly from the inner edge of the frame'E. The pins 48 and 50 thus providea-universalconnec tion at the Wrist portion 39 of the artificial limb to thus enable movement of the hand'from;side' to side or forwardly and rearwardly.

Coil'springs 52 extend longitudinally intowrist portion 38 and connect the inner ends of the frame 5 at the front, rear and side portionsthereof "to corresponding portionsof the socket 45, the:

springs exerting their influence on the hand to normally maintain the same in an extended position at the outer end of the socket 45.

,Each finger and thumb is provided'withan artificial fingernail 53 formed with a fiangeid' at its edges for removable insertion in recesses- 55 at the tips of the fingers and thumb, the nailsbeing colored to simulate natural finger nails. The fingernails are removable for cleaning; whendesired.

' In the operation of the device. withz'theiwrist 39 attached to the=socket G5'asindicated andzthesocket secured to the: stump of a forearm'as shown in Figure 3 the flexible covering: 1' forrthe' hand and wrist will enablethe springsi3rl atrtheseveralphalanges of the fingers andthumb'to maintain the fingers and thumb in anextendedi position,Whentheiarmof, the person is bent .at.

the; elbow; However. upon straightening; of. the

arm at the elbow a1 pulling actionwill be,;im,-

partedxato ;the;w.ires leading to the 'outer phalangesgof the fingersand thumb therebycausing the fingers and thumb to close-inwardly against thepalm of the handasshownin Figure 1 of the drawings and thefingersand thumbzmay :then be used to grip an objectto be'carriedrby'rthe antificialzhand; r

The universal joint at the wrist of the artificial limb will enable the hand to flex from side to side or forwardly and backwardly when the hand is subjected to lateral pressure. 7

In view of the foregoing description taken in, conjunction with the accompanying'drawings it" is believed that a clear understanding of the device will be quite apparent to those skilled in th s art. A. more detailed descriptiomis accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention the same issusceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claims.

Lolaimz.

1. An artificial hand comprising a hand portion and a wrist portion, said hand portion including a rigid skeleton frame and said wrist portion including a rigid socket for receivingthe stump of a forearm, a covering of yi-eldable' material enclosing said frame and socket, a universal spring biased connection between the frame and the socket normally sup-porting the hand in an extended position, said hand also including bend= able fingers which are solid except for relatively small irregularly shaped bores therein, jointed cores for the :bores in said fingers, and flexible means extending rearwardly from the outer'ends of the cores and connected to a persons arm above the elbow and operable to close andtb open the fingers upon a flexing of the arm at the elbow.

2. An artificial hand comprising a hand portionand a wrist portion, said hand portion including a rigid skeleton frame and said wrist portion including a rigid socket for receiving the stump of a forearm, a covering of yieldable material enclosing said frame and socket, a universal spring biased connection between the frame and? the socket normally supporting thehand inan extended position, said hand also including bendable fingers which are solid except for relatively small irregularly shaped bores therein jointed cores for the bores in said fingers, means pivotally connecting the inner ends of the cores to .the. frame, and fiexiblemeans extending rearwardly from the outer ends of the cores andconnectedto a persons arm above the elbow and operablejo said hand portion including. a rigid. skeleton. frame, a bracket at the outer end .of. said...socket" having spacedv apart; aligned eyes,.,a pivot,.c.on= necting the plate .to the eyes at its-oppDsiteside: edges, a yoke extending inwardlyfrom the skeleton frame of the hand portion and straddlingxthe':

plate, and a pivot connecting theyoke to. the plate, said first and last named pivots. being. at. right angles to. each other..

4. In an artificial limb wrist andlhandlportion's saidwrist portion includinga rigid,socket and said hand portion including a. rigidv skeleton. frame, a bracketat the outer. end.of saids.ocket having spaced apart alignedeyes,a.pivot.con-

necting thevplate to the eyes. at itsopposites'ideedges, a yoke extending inwardly from.the..skeleton frame of the hand portionandstraddling,

the plate, and a pivot connecting theyoke to the. plate, said first :and last-named pivots. [being at 1. right. angles .to each other, coil springs connecting,

5 the socket to the frame and extending longitudinally of the wrist at the front, rear and sides thereof, a covering of yieldable material for said socket and wrist portion, and a covering for said hand portion integral with the first mentioned covering.

5. In an artificial hand, fingers of a flexible material and solid except for a relatively small bore therein to house actuating means therefor, and fingernails having raised central portions and flanges on rear and side edges, said fingers having recesses for removably receiving said flanges.

WILLIAM G. FARRAR, JR.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number 6 UNITED STATES PATENTS Name it Date Stofiel Jan. 10, 1865 Spellerberg Nov. 28, 1865 Aydt Feb. 14, 1911 OConnor Sept. 3, 1918 surry Feb. 26, 1924 Laherty Oct. 10, 1933 Eberle Feb. 4, 1941 Horn June 17, 1947 FOREIGN PATENTS Country Date Italy Apr. 25', 1938 

